Acute myeloid leukemia (AML) has been treated with combination chemotherapy, hematopoietic stem cell transplantation (HSCT) and differentiation induction therapy. Intensive induction and consolidation therapy including high dose cytarabine (HDAC) is a widely used combination in chemotherapy in the USA and European countries. In Japan, the efficacy of HDAC needs to be evaluated under a good clinical trial. Stem cell source for HSCT has been expanded, and the number of peripheral blood stem cell transplantations is greater than that of bone marrow transplantation, especially for auto-transplantation. Despite some randomized clinical trials, we still do not know whether HSCT provides longer survival than chemotherapy for patients with AML when performed during their first remission. Differentiation therapy for acute promyelocytic leukemia (APL) using ATRA showed clear success in the treatment for AML. APL is stratified with its specific karyotype and morphology, and this stratification leads to the improvement of overall survival of patients with APL. Several clinical study groups in the world have studied prognostic factors and it has been shown that the chromosomal abnormality of AML cells is closely related to the response to the chemotherapy. The stratification of AML using these prognostic factors is incorporated in some clinical trials to determine whether this approach actually leads to better survival for patients with AML.